高温质子交换膜燃料电池机理模型研究进展

建立高温质子交换膜燃料电池的机理模型可以加深对其内部传递现象和反应机理的认识,同时可以预测不同参数下燃料电池的性能,对优化电池的操作条件和结构参数等具有重要的指导意义。对现有的高温质子交换膜燃料电池机理模型进行了评述,分析了基于磷酸掺杂聚苯并咪唑膜(H3PO4/PBI)不同维数的稳态和动态模型及基于其他复合膜模型的优点和不足,并指出了高温质子交换膜燃料电池模型的研究方向。     

高温质子交换膜研究进展

高温质子交换膜燃料电池解决了传统质子交换膜燃料电池催化剂易受CO等杂质气体毒化、水热管理复杂等问题,成为当今燃料电池发展的主要方向。高温质子交换膜是实现高温操作的关键部分。本文结合质子传递机理,分析了以水作为质子溶剂、非水质子溶剂质子交换膜以及无机固态质子导体膜的研究现状,认为有机/无机复合膜和非水质子溶剂膜,尤其是其中的磷酸掺杂的PBI膜是高温质子交换膜的发展方向。     

高温质子交换膜研究进展

高温质子交换膜燃料电池（HT-PEMFCs）因其具有催化剂CO耐受性良好,能量转化率高,水热管理简单等优点,成为了能源领域重要的研究方向之一。高温质子交换膜（HTPEM）是它的主要部件之一,分别以水、磷酸分子和咪唑分子为质子传导载体分析了目前HTPEM的研究现状,比较后得出了以磷酸为质子载体的HTPEM性能最佳的结论,指出了研究中尚存的问题,并展望了未来HTPEM可能的研究方向。     

燃料电池高温质子交换膜研究进展

高温质子交换膜燃料电池具有反应动力学快、CO耐受性高等特点,但磷酸掺杂的高温质子交换膜因磷酸的流失和聚合物的降解等原因导致燃料电池的输出功率发生衰减。本文通过介绍聚苯并咪唑衍生物的高温质子交换膜、聚苯并咪唑的复合型质子交换膜、新型芳基聚合物的高温质子交换膜,阐明聚合物的主链结构、官能团结构以及复合填料对高温质子交换膜性能的影响。在近期的研究报道中,提高膜性能的主要策略包括提升自由体积、建立交联结构、嵌段共聚、复合掺杂（ILs、MOFs、PIMs、MO_x）、阳离子官能团修饰等。文章指出,在未来的研究中应该加强对磷酸基高温质子交换膜质子传输通道结构的进一步理解,关注聚合物化学降解和物理性能衰败的原因,并开发更多的新型聚合物材料。     

质子交换膜燃料电池关键技术研究进展

简述了质子交换膜燃料电池(PEMFC)的工作原理及特点;综述了PEMFC关键技术的最新研究进展,包括质子交换膜合成、电催化剂制备、膜电极工艺及水管理和热控制;并简介了我国PEMFC的开发情况。     

大功率质子交换膜燃料电池电堆膜电极一致性研究

随着燃料电池应用领域的拓宽以及应用规模的不断扩大,大功率燃料电池电堆的需求也不断上升。大功率燃料电池电堆的电压一致性是衡量或影响电堆性能的重要指标。对某公司生产的65 kW大功率电堆进行了单电池一致性的研究,考察不同运行条件对于电堆一致性的影响,并对其产生的可能原因进行了深入的研究和讨论。研究结果表明：在额定功率和给定的运行条件下,电堆表现出了较好的一致性;电堆输出功率、电堆温度和温差、反应气体计量比、气体湿度等对电堆膜电极一致性均有较大的影响。其中输出功率、空气计量比、气体湿度对于电堆一致性的影响最为强烈,输出功率增高、空气计量比和空气湿度降低均会大幅度降低电堆的一致性。在研究结果的基础上,提出了保持大功率燃料电池电堆一致性的运行条件的建议。可为改善大功率电堆的设计和优化大功率电堆的运行条件,及促进我国燃料电池技术及产业的发展提供参考。     

用于高温质子交换膜燃料电池的聚合物电解质膜研究进展

高温质子交换膜燃料电池在降低燃料电池水热管理复杂性、催化剂中毒方面有明显优势;可改善电池阴阳两极尤其是阴极氧气还原反应的动力学特性,提高电池的效率。聚合物电解质膜作为关键材料之一,在高温时易失水导致质子传导率降低、机械强度和热稳定性不高等问题。本文基于磺酸、磷酸和离子液体等不同质子传递介质,对高温聚合物电解质膜进行综述,比较了各类聚合物电解质膜的优缺点及应用时存在的问题,着重探讨嵌段共聚物在高温聚合物电解质膜方面的潜在应用,指出离子液体的添加不但可作为质子载体,而且在构建嵌段聚合物结构方面可发挥"诱导剂"作用。提出通过分子设计可更好了解嵌段聚合物的空间构效关系,进而通过结构设计提高膜的质子传导性能和稳定性。     

质子交换膜燃料电池加氢反应器

简述了燃料电池反应器的研究现状,根据膜反应器的设计思想,提出质了交换膜燃料电池加氢反应器的新概念,阐述了质子交换膜燃料电池作为加氢反应器的原理、可行性及应用前景。     

燃料电池质子交换膜研究进展

质子交换膜作为燃料电池的关键材料之一,得到世界各国学者的广泛关注和深入研究,已先后研发出含氟高分子类、芳香烃聚合物类以及有机/无机杂化材料的质子交换膜.本文对燃料电池工作原理进行简要概述,并针对质子交换膜的应用前景及研究现状进行分析.     

Dissolution kinetics of lead from a lead-oxide ore that consists mainly of cerussite by trichloroacetic acid and optimization of dissolution conditions

The dissolution kinetics of lead-bearing ore in trichloroacetic acid (TCA) solution were investigated. The effects of various parameters were studied to optimize the dissolution conditions and to determine the leach kinetics. An increase in leaching time, temperature, and TCA concentration, and a decrease in particle size enhanced the conversion rate. The results show that 99.26% of lead content was extracted from the samples with particle size range of –90 + 75 µm after 24 min leaching in 0.4 mol/L TCA at 800 rpm and 40°C. The following expression based on the Jander (three-dimensional) model can be described: [1–(1–x)^1/3]2 = 22.36 × 10^?3 (C_TCA)^1.1516(P)^0.55117(r)^0.92609exp (–20899/RT) t.     

Investigation of phosphoric acid and water transport in the high temperature proton exchange membrane fuel cells using a multiphase model

A three-dimensional, nonisothermal, and multiphase model of high temperature proton exchange membrane fuel cells is built to investigate water and phosphoric acid transportation, in which a spherical agglomerate model considering catalyst layer structure and liquid saturation is applied to determine the electrochemical kinetics in the cathode catalyst layer. Experimental polarization curve, water proportion in the anode outlet gas, and phosphoric acid distribution are selected for validation. It is found that the simulated results can represent the experimental data with reasonable accuracy. Based on the model, the effects of current density and stoichiometry on the variable distributions are analyzed. The results show that water in anode is mainly from cathode by concentration diffusion of liquid water, and the proportion of anode outlet water to the total produced water decreases slightly with the increase of current density. A higher current density leads to a greater electromigration of phosphoric acid from cathode to anode and a higher liquid phase fraction in anode, while a lower phosphoric acid concentration in the fuel cells.     

酸法浸铀与生物浸铀浸泡试验的对比研究

近年来,生物技术在我国低品位砂岩型铀矿及老采区残留难浸铀矿的开发研究已开始起步。凭借生物浸铀具有的氧化性强、浸出液铀浓度及浸出率高等特点而成为开采该类铀矿的重要手段。文章以新疆某砂岩型难浸铀矿石浸泡浸出试验为例,系统开展了不同酸度条件下酸法浸出及不同Fe3+浓度条件下细菌浸铀试验。试验结果表明,生物浸铀在浸出液平均铀浓度、铀浸出率及浸出量等方面均高于酸法试验结果。     

硫酸浸取硫铁矿烧渣工艺条件的优化

对硫酸浸取硫铁矿烧渣反应进行了实验研究,探讨了影响浸取反应的影响因素。主要考察了反应温度、反应时间、硫酸浓度及硫酸用量过量系数对铁浸出率的影响,通过4因素4水平正交试验得出各种影响因素的极差值依次为：反应温度（0.212）、时间（0.075 5）、过量系数（0.062 5）、浓度（0.057 7）,其中温度影响最为显著。优化的工艺条件温度为100 ℃、时间为3 h、过量系数为1.05、浓度为8 mol/L,实际操作中由于温度在100 ℃时不便于控制,可以采用微加压更有利于浸出率的提高。      

Performance Analysis of a HT-PEMFC System with 6FPBI Membranes Doped with Cross-Linkable Polymeric Ionic Liquid

In this paper, a high-temperature proton-exchange membrane fuel cell (HT-PEMFC) system using fluorine-containing polybenzimidazole (6FPBI) composite membranes doped with cross-linkable polymer ionic liquid (cPIL) is developed and studied. The reliability of the model is verified by a comparison with the experimental data. The performance of the HT-PEMFC system using 6FPBI membranes with different levels of cPIL is analyzed. The results show that when the HT-PEMFC uses 6FPBI membranes with a cPIL content of 20 wt % (6FPBI-cPIL 20 membranes), the single cell power density is 4952.3 W·m−2. The excessive cPIL content will lead to HT-PEMFC performance degradation. The HT-PEMFC system using the 6FPBI-cPIL 20 membranes shows a higher performance, even at higher temperatures and pressures, than the systems using 6FPBI membranes. In addition, the parametric study results suggest that the HT-PEMFC system should be operated at a higher inlet temperature and hydrogen pressure to increase system output power and efficiency. The oxygen inlet pressure should be reduced to decrease the power consumption of the ancillary equipment and improve system efficiency. The proposed model can provide a prediction for the performance of HT-PEMFC systems with the application of phosphoric-acid-doped polybenzimidazole (PA-PBI) membranes.     

FeCoCa氧化物纳米晶的制备及芬顿降解亚甲基蓝的性能分析

采用溶胶-凝胶法制备了FeCoCa三种元素的氧化物纳米晶.采用XRD,SEM对催化剂进行表征,同时研究了亚甲基蓝催化剂与H2O2的协同降解作用.结果表明:FeCoCa氧化物纳米晶和H2O2组成的Fenton反应可以有效地降解亚甲基蓝溶液;当铁钴钙三种元素的摩尔比例为1∶i.5∶3.5,催化剂投加量为1.2 g/L,过氧化氢投加量为0.7mL,初始pH值为6.80,亚甲基蓝的降解率达到93％;与传统Fenton反应体系相比,溶出铁的量降低到0.18 mg/L.     

废旧磷酸铁锂正极粉磷酸浸出过程的优化及宏观动力学

随着新能源汽车产业快速发展,磷酸铁锂动力电池退役量爆发式增长,回收需求迫切,但面临回收利用经济性较差的难题。正极材料价值较高,本文提出采用磷酸浸出废旧正极材料以制备电池用磷酸铁,但铝等杂质的分离是关键。本文以含铝的磷酸铁锂正极粉为原料,开展了磷酸浸出过程优化及宏观动力学研究,重点研究了酸料比、浸出温度、液固比、搅拌速度等参数对磷酸铁锂及铝浸出效果的影响规律,并考察了磷酸铁锂在磷酸溶液中浸出的宏观动力学。研究结果表明,在酸料比1.1mL/g、温度20℃、液固比（5∶1)mL/g、搅拌速度400r/min、浸出时间120min条件下,磷酸铁锂浸出率大于93%,铝浸出率小于20%;磷酸铁锂正极粉磷酸浸出过程符合无固态产物层的收缩核模型,表观活化能为24.62kJ/mol,浸出过程受扩散控制。     

Thermodynamic Modeling and Exergy Analysis of A Combined High-Temperature Proton Exchange Membrane Fuel Cell and ORC System for Automotive Applications

A combined system consisting of a high-temperature proton exchange membrane fuel cell (HT-PEMFC) and an organic Rankine cycle (ORC) is provided for automotive applications in this paper. The combined system uses HT-PEMFC stack cathode exhaust gas to preheat the inlet gas and the ORC to recover the waste heat from the stack. The model of the combined system was developed and the feasibility of the model was verified. In addition, the evaluation index of the proposed system was derived through an energy and exergy analysis. The numerical simulation results show that the HT-PEMFC stack, cathode heat exchanger, and evaporator contributed the most to the total exergy loss of the system. These components should be optimized as a focus of future research to improve system performance. The lower current density increased the ecological function and the system efficiency, but reduced the system’s net out-power. A higher inlet temperature and higher hydrogen pressures of the stack and the lower oxygen pressure helped improve the system performance. Compared to the HT-PEFC system without an ORC subsystem, the output power of the combined system was increased by 12.95%.     

活性氧化锌生产工艺评价与研究

通过研究,对现行活性氧化锌的生产工艺加以比较、评价,指出改进意见,重点对氯化铵浸取法进行了深入研究。